Stacking apparatus



July 6, 1943.

G. s. SILLARS STACKING APPARATUS 3 Sheets-heeb 1 Filed Dec. 5, 1941 July 6, 1943. e. s. SILLARS STACKING APPARATUS Filed Dec. 5, 1941 3 Sheets-Sheet 2 y 1943- a. s. SILLARS 2,323,359

- STACKI'NG APPARATUS Filed Dec. 5, 1941 s sheets sheet s Patented July 6, 1943 UNiTEID STATES PATENT OFFICE 20 Claims.

The present invention is concerned with apparatus for stacking or arranging in a series various articles. Especially is this invention applicable to the nesting of such walled articles as box-parts, including either the body-portions or covers. Hereinafter in the detailed description, these parts are generally referred to as covers. In the manufacture of set-up box-parts, after they have been formed and their walls secured, it is a common practice to nest them in stacks, so. they may be transferred conveniently to some other point, as that at which they are packed in cases. Since the walls of these parts are ordinarily parallel, they can be nested at one extremity only, each part lying within the preceding part in the stack at one end and projecting outside it at the opposite end. This projecting portion in turn receives the succeeding part. It is an object of this invention to effect the stacking of the boxparts automatically, by sensitive means which operates accurately under the direct control of such parts and which is so free from complication that it is relatively inexpensive and easy to maintain.

For the attainment of this object, I combine with a support and means for advancing boxparts successively in a series to the support, means for stopping the box-parts alternately in different positions at the support, means acting upon each part at the stopping means to assemble them in a stack upon the support, and means controlled by the box-parts for governing either the stopping means or assembling means, or both of these instrumentalities. This governing means preferably consists of a light-sensitive device, as a photoelectric cell, the reception of light by which is varied by the box-parts themselves, but without calling for the exertion of any force. In the illustrative embodiment of the in vention, a conveyor for box-parts is movable over a stacking table, and a stacking member reciprocates across the conveyor. Stop members, shown as furnished by arms extending at difierent angles from a rotatable shaft and at different points along the conveyor, determine alternately positions at which the box-parts receive the action of the stacking member, A beam of light i directed across the conveyor at the stacking member upon a photoelectric cell at the opposite side, this cell acting under the influence of the presonce or absence of light varied by the delivered box-parts themselves and governing the energize.- t on of the moving means, which may be in the form of a solenoid. Contact members appear extending above the conveyor and the stack-receivward extension 18.

ing portion of the. table for engagement with the arriving box-parts and. with the accumulating stack, these members preferably being mounted upon a vertically adjustable support and being connected to each other. One element of the controlling means, as the light-source, may be carried upon the support, so, as an adjustment of the contact members. is made for work of different sizes, the controlling means is correspondingly positioned.

As another feature of the invention, I provide a member movable to compact. the forming, stack, so it may be more securely nested and more readily disposed of, this member being moved under the control of the box-parts advanced for stacking. The control may be exercised by the same means as that which governs the stopping means and assembling means, the photoelectric cell or other light-sensitive device, when effected by the box-parts, causing the energization of a solenoid which actuates the compacting member.

In the accompanying drawings is shown a single embodiment of the invention,

Fig. 1 being a front elevation thereof;

Fig. 2, a side elevation, looking from the right in Fig. 1;

Fig- 3, a partial top plan view, somewhat diagrammatic in character;

Fig. 4, a detail in perspective of the ratchet mechanism for. positioning the stop-arms; and

Fig. 5, a diagram of the electrical circuit.

A base l-0 has rising from its front and rear,

respectively, standards !2 and I4, between which is supported a horizontal table i6, having a rear- Running over the table and extension upon a pair of pulleys, one of which appears at 20 carried by a shaft 2|, .is an endless conveyor-belt 22. The conveyor may be operated continuously by belt gearing 24. Upon the upper run of the conveyor is advanced a series of articles, to be stacked or nested, as covers C of the type used upon shoe-boxes. These may be delivered to the conveyor one by one, for example, manually by an operator who is forming them upon a setting-up machine. They are supplied to the conveyor upon their longitudinal edges, with their open or undersides toward the observer in Fig. 2. Vertical walls 26, 26, mounted at opposite sides of the table-extension l8 upon brackets 28, maintain the covers upright, until they are received in stacking position upon the table It. An upper wall or cover-plate 30, parallel to the table-extension, is connected to the side-walls by brackets 32, and'serves to hold the series of covers against upward displacement as they are urged forward by the conveyor. To accommodate the upper wall to covers of different widths, the brackets 32 may be adjusted vertically by slot-and-screw connections 34. Upon the underside of the cover-plate at the right of the conveyor (Fig. 1) a guide-strip 35 is attached by a screw and thumb-nut 38, passing through a longitudinal slot in the strip and through the cover-plate. The strip is preferably inclined forwardly and inwardly (Fig. 3) to direct the covers into a uniform tacking position upon the table I6. The slot-and-screw connection permits the forward extremity of the strip to be placed in the correct relation to the stacking mechanism for covers of different lengths.

Above the table I6, the advance of the covers is variably limited by stop mechanism S. Rotatable in a standard 42, carried by the base I0 at one side of the standard I2 and in a standard 44 spaced from it, is a horizontal shaft 46. Upon this are secured, across the table I6 from the extension I8, two pairs of oppositely projecting stop-arm's 48, 48 and 50, 50. The arms of each pair are separated about the shaft, by 180, while the arms of each pair are separated from those of the other pair by 90. The two pairs are spaced from each other longitudinally of the shaft by such a distance that covers, successively delivered for stacking, will be stopped in different positions across the table. As a result of this, when the covers are forced into the stack, the opposite ends of successive covers will alternately enter the covers in advance, as appears in Fig. 3. To thus present the arms to stop the covers, the

shaft 46 is rotated in successive steps through 90.

Thus, if an arm 48 is effective, as appears in the drawings, one of the arms 50 will next come into cover-stopping relation. To accomplish this, the shaft 46 is joined by sprocket-gearing 52 to a shaft 54 journaled, just above the base I0, in the standards 42 and 44 and still another standard 56. As is best shown in Fig. 4, a sprocket-wheel 58 of the gearing 52 is fast upon the shaft54, as is also an adjacent ratchet-wheel 60. Between the ratchet-wheel and a collar 62 fixed upon the shaft is a carrier 64, arranged to turn about the shaft. Plvoted at 66 upon the carrier is a pawl 68, urged into engagement with the teeth of the ratchet-wheel by a spring I0 connecting it to said carrier. Journaled above .the base parallel to the shaft 54 is a shaft I2, from which projects an arm I4 connected by a link I6 to the pawl 68. The shaft I2 also has secured to it an arm I8, which is joined by a link 8|) to the plunger 82 of a solenoid 84. When the plunger is drawn down, the arms I8 and I4 are turned clockwise (Fig. 1), and the pawl 68 is moved idly over the teeth of the ratchet-wheel 60. Upon opposite movement of the plunger under the force of a tension-spring 86 by which it is connected to the base I0, the pawl engages a tooth of the ratchet-wheel to rotate the sprocket-wheel 58. This, through the gearing 52, turns the shaft 46 through 90 carrying a stop-arm of one pair out of active position and rendering an arm of the other pair effective. The manner of energizing the solenoid will later be described. 7

When the leading cover of the series upon the conveyor 22 is against a stop-arm 48 or 58 of either of the pairs, it is opposite the stack-supporting surface of the table I6, and is alined with ahorizontally reciprocatory transferring and stacking plunger or head H. This head has a vertical portion 90, to which are attached horizontal upper and lower crossbars 92 and 94, re-

spectively. The upper bar has, at the end toward the incoming covers upon the conveyor 22, an outward extension 96 (Fig. 3), which, when the head is making a transfer, crosses the path of the covers and holds back the series following the one being operated upon. From the opposite extremity of the upper bar is an extension 98, of such length that, when the head is drawn back in preparation for the'transfer of the succeeding cover, its vertical end-surface I00 abuts against one edge of a square block I02 secured to the shaft 46. The angle at which the block lies about the shaft is such, that when the surface I00 of the bar presses against it, the stoparm, which is to be effective, will be turned to the true horizontal relation, if for any reason, as

because of 10st motion in the sprocket-gearing, its actuating mechanism has not properly positioned it. The portion 90 of the head H rises from a slide I04, guided in horizontal ways I06, I06 upon the top of the table l6. A link I08 joins the slide to an arm IIO attached to the shaft I2. When the shaft is turned by the action of the solenoid 84 to produce the idle movement of the pawl 68, the slide I04 is advanced, and the cover C, which has been arrested by one of the stop-arms 48 or 50, is engaged by the head and transferred to the stacking surface of the' table. Upon de-energization of the solenoid, the head is retracted by the spring 86, and, during this movement, the stop-arms are changed by their rotation to position the succeeding cover.

The cover is transferred by the head H from the conveyor to the surface of the table between opposite side-walls H2 and H4. The wall II2 may be carried upon a slide I I8 movable in ways I20, I20 beneath the table. At the underside of the slide is 9. lug I22, through which is threaded a screw I24 mounted to rotate beneath the table. By turning the screw through a hand-wheel I26 fixed to its forward extremity, the wall 2 may be adjusted toward or from the opposite wall for the reception of covers of different lengths. Intothe space between the walls the covers may be directed by an expanded portion or throat, formed by an outwardly and rearwardly inclined end I2'I upon the wall II2 (Fig. 3). The Wall II4 first converges outwardly toward the wall I I2 and is then substantially parallel to it, being movable transversely to urge together the nested covers. By this means, the adjacent ends of succeeding covers are carried toward each other, thus rendering the stack more compact and easier to handle. For this purpose, the wall H4 is attached to the upper ends of a pair of substantially vertical arms I28, I28, secured to a shaft I mounted to oscillate just above the base I0. Depending from the shaft is an arm I32, joined at I34 to the plunger I36 of a solenoid I38 supported beneath the base. A tension-spring I40 acts to draw the wall 4 normally in and the plunger I36 out of the solenoid. This solenoid is energized simultaneously with the solenoid 84, the effect being to withdraw the wall from the path of the cover advanced by the head H. Then, upon de-energization of the two solenoids, the head is retracted, and the wall drawn in by the spring into contact with the ends of the covers. The accumulated stack is thereby compacted laterally, and, on account of the convergence of the walls 2 and H4, the effect is gradual, the adjacent cover-ends being gently wedged together as the stack is formed. Therefore, it emerges from between the walls upon the table as a securely joined column ready for handling.

To exert a retardin effect upon the covers as they are advanced by th head H upon the table and hold them sufficiently to allow the stack to form, contact means R extends along the upper edges of the accumulated covers substantially parallel to the table. Mounted for vertical adjustment upon the standards l2 and I4 by clampscrews I4I, MI is a bridge-piece I42 spanning the table. Secured to the bridge-piece, above and approximately midway between the walls I I2 and I I4, is a contact-bar Hi4, the underside of which, nearest its inner portion, is inclined downwardly and outwardly. Carried upon the bridge-piece at each side of and parallel to the bar is a brush I46, the ends of the fibers of which lie somewhat below the inclined surface of the bar. As the covers are thrust successively from the conveyor 22 by the head H, their upper edges first engage the brush-fibers at opposite sides of the center. Each cover is thereby held in position until it is advanced by the nesting with it of the following cover. This continues until a section of the stack having some stability is formed. Thereafter, the stack is steadied by the contact with it of the bar I44. When the vertical dimension or width of the covers varies, the retarding means B may be adjusted to give the desired effect by raising or lowering the bridge-piece. The bar I44 and the cover-plate 3B are preferably joined at I43 to move together, and, when the adiustment is made at IGI, the adjusting means 34 is correspondingly varied.

Reference has already been made to control of the energization of the solenoid 84 by which the stop mechanism S is positioned, and the transferring head H reciprocated. The principal elements of the controlling means appear in Figs. '1 and 2, and the general system is illustrated diagrammatically in Fig. 5. Carried by a bracket I50 upon the base IE is a light-sensitive device, which may be in the form of a photoelectric cell, the enclosing casing of which is shown at I 52. Upon the bridge-piece I42 a source of light I54 is mounted, a beam of light emitted thereby, and indicated by a dash-line I55, being projected across the path of the covers as the conveyor 22 carries them against either of the stop-arms -8 or 5!]. Variations in the potential produced in the photoelectric cell by the impingement upon it or the interruption of the light-beam, affect an amplifying relay, indicated at I55, to either cut off or supply current to the solenoids 8d and I38 from a relatively high potential source applied to the circuit at I53. Before a cover C arrives against one of the stop-arms 48 or 53 following the removal of the preceding cover, the energizing circuit of the solenoids is held open at the contacts of the relay I55. When, however, the succeeding cover crosses the light-beam I55, the drop in potential in the cell I52 causes the release of the relay to supply current to the two solenoids. To permit the cell to be best located for covers of different widths, its bracket I 53 may be adjustably attached to the base by slot-andscrew connections I59.

For the particular length of cover 0 to be stacked, the strip will be adjusted along theconveyor 22 to guide an advancing cover properly into stacking position, and the wall I 2 correspondingly located. The cover-plate 3i} and retarding means R are raised or lowered together in accordance with the width of the cover. Since the source I54.- of light moves with the bridge-piece I42, which carries the vertically adjusted elements, the light-beam will be kept in the proper relation to be intercepted by the cover for which the adjustment was made. The drawings show an arm 48 in active position in the path of the leading cover in the series upon the conveyor supplied from the setting-up machine. When the cover interrupts the light-beam I55, the normally de-energized solenoid 84 acts under the control of the photoelectric cell I52 and the released relay I56 which it governs. The transfer head H is carried forward by its connections to the plunger 82 of the solenoid 84, to remove the cover from the conveyor and deposit it upon the table I6 between the walls H2, H4. Because a stop-arm 48 was active, the right-hand end of the delivered cover, as viewed in Fig. 3, will be close to the wall H2. During this transfer, the pawl 58 will have been turned idly clockwise over the ratchet-wheel 653 (Fig. 4), by its connection to the plunger of the solenoid 85. Upon the transfer of the cover by the head H from the conveyor to the table, the freeing of the light-beam will cause the photoelectric cell to energize the relay I56, de-energizing the solenoid. The head will be returned to its initial position by the spring 86, and at the same time the pawl $3 will engage the ratchet-wheel and through the sprocket-gearing 52 will turn the shaft 46 through This brings a stop-arm 50 into active position, the desired relation being assured by the contact of the surface I08 upon the headextension 93 with one of the edges of the block I02 upon the shaft 48. The succeeding cover is thereby allowed to advance farther, so upon its transfer by the head H its left-hand end (Fig. 3) will be close to the wall I I l. The covers are thus nested alternately in oppositely inclined relation. Simultaneously with the solenoid 84, the solenoid I38 was energized. This oscillates the shaft I30, so that as the covers are nested, they will be forced by the Wall I is toward the wall I I2 to give a firmly assembled stable stack. Now, as this stack accumulates, a portion at the forward end may be removed from the table, as desired, by the attendant. In spite of the fact that the covers are relatively light, offer, little resistance to distortion and slip readily upon the belt 22, their individual action upon stacking mechanism is entirely efiective, because, with the light-sensitive controlling means, no mechanical stress is imposed upon them.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In an apparatus for stacking box-parts, a support, means for advancing box-parts successively in a series to the support, means for stopping the box-parts alternately in positions advanced to diiferent extents at the support, and means controlled by the box-parts and acting upon each part the stopping means to assemble them in a stack upon the support.

2. In an apparatus for stacking box-parts, a support, for advancing box-parts successively in a series to the support, means for stopping the box-parts alternately in different positions at the support, means controlled by the advancing box-parts for governing the stopping means, and movable means acting upon the boxparts at the stoppin means for moving said boxparts to form a stack.

3. In an apparatus for stacking box-parts, a support, means for advancing box-parts succes- .cly in a series to the support, means for stopping the box parts alternately in diiierent positions at the support, means acting upon the stopped box-parts for assembling them in a stack, and means controlled by the advancing box-parts for governing both the stopping means and the assembling means.

4. In an apparatus for stacking box-parts, a support, means for advancing box-parts successively in a series to the support, means for stopping the box-parts alternately in different positions at the support, means acting upon the stopped box-parts for assembling them in a stack; and light-sensitive means controlled by the boxparts for governing both the stopping means and assembling means.

5. The combination with a table, of a conveyor for delivering successively above the table walled box-parts capable of nesting, means for stopping the box-parts alternately in diiferent positions upon the table, a member movable over the table and forcing each box-part from the conveyor and. into nested relation with the preceding box-part upon the table to form an unbroken stack, means for moving the stack-forming member, and a photoelectric cell the reception of light by which is varied by the box-parts to control the moving means.

6. The combination with a stationary table, of a conveyor for delivering successively to the table Walled box-parts capable of nesting and on edge with their openings at one side, means for stopping the box-parts alternatel in different positions upon the table, a member movable over the table in engagement with the box-parts to nest them and form a stack, means for moving the stack-forming member, and a photoelectric cell the reception of light by which is varied by the box-parts delivered to the table to control the moving means.

'7. The combination with a table, of a conveyor for delivering box-parts successively to the table, a member movable over the table in engagement with the box-parts to form a stack, two stops by which the box-parts are differently positioned at the table with reference to the stackforming member, and means for renderin the stops alternately effective.

8. The combination with a table, of a conveyor for delivering box-parts successively to the table, a member movable over the table in engagement with the box-parts to form a stack, two stops by which the box-parts are difierently positioned at the table with reference to the stack-forming member, and means controlled by the delivered box-parts for rendering the stops alternately effective.

9. The combination with a table, of a conveyor for delivering box-parts successively to the table, a member movable over the table in engagement with the box-parts to form a stack, two stops by which the box-parts are differently positioned at the table with reference to the stack-forming member, and a photoelectric cell the reception of light by which is varied by the box-parts to control the position of the stops.

10. The combination with a table, of a conveyor for delivering box-parts successively to the table on edge with their openings at one side, a member movable over the table in engagement with the box-parts to nest them and form a stack, two members by which successive box-parts are stopped alternately in difierent positions across the stackforming member, and a photoelectric cell the reception of light by which is varied by the box-parts delivered at the table to thereby govern the stop members and the movement of the stack-forming member.

11. In a stacking apparatus, a table, a conveyor movable over the table, two stop members movable alternately into and out of position above the conveyor at the table, a reciprocatory stacking member movable across the conveyor at the receiving side of the stops, and means controlled by an article upon the conveyor for governing the position of the stops and the movement of the stacking member.

12. In a stacking apparatus, a table, a conveyor movable over the table, two stop members movable alternately into and out of position above the conveyor at the table, a reciprocatory stacking member movable across the conveyor at the receiving side of the stops, means for directing a light-beam across the conveyor at the stacking member, a photoelectric cell at the opposite side of the conveyor and from which an article stopped for stacking cuts off the beam of light, and means controlled by the photoelectric cell for governing the position of the stops and the reciprocation of the stacking member.

13. In a stacking apparatus, a table, a conveyor movable over the table, two stop members movable alternately into and out of position above the conveyor at the table, a reciprocatory stacking member movable across the conveyor at the receiving side of the stops, means for directing a light-beam across the conveyor at the stacking member, a photoelectric cell at the opposite side of the conveyor and from which an article stopped for stacking cuts 01? the beam of light, and means controlled by the photoelectric cell for first actuating the stacking member and then shifting the position of the stops.

14. In a stacking apparatus, a table, a conveyor movable over the table, a stacking member reciprocating across the conveyor, a shaft rotatable adjacent to the conveyor and having arms extending therefrom at different angles and at different points over the conveyor, and means operating upon the arrival of an article to be stacked at the stacking member for governing the movement of the stacking member and the rotation of the shaft.

15. In a stacking apparatus, a table, a conveyor movable over the table, a stacking member reciprocating across the conveyor, a shaft rotatable adjacent to the conveyor and having arms extending therefrom at different angles and at difierent points over the conveyor, ratchet mechanism through which the shaft is rotated, and means for moving the stacking member across the conveyor and simultaneousl moving the ratchet mechanism idly and then retracting the stacking member and actuating the ratchet mechanism to rotate the shaft.

16. In a stacking apparatus, a table, a conveyor movable over the table, a stacking member reciprocating across the conveyor, stops movable into position above the conveyor at difierent points beyond the stacking member, members for contact with articles being stacked extending above the conveyor and above the table opposite the stacking member, said members being joined to each other, and a support for the members variable in position vertically.

17. In a stacking apparatus, a table, a conveyor movable over the table, a stacking member reciprocating across the conveyor, stops movable into position above the conveyor at different points beyond the stacking member, a support extending across the stack-receiving portion of the table, means arranged to vary the position of the support toward and from the table, a device mounted upon the support for contact with articles being stacked, and means controlling the movement of the stacking member and of the stops and having portions situated at opposite sides of the conveyor, one of said portions being carried by the support.

18. In a stacking apparatus, a table, a conveyor movable over the table, a stacking member reciprocating across the conveyor, stops movable into position across the conveyor at difierent points beyond the stacking member, a support extending across the stack-receiving portion of the table, means arranged to vary the position of the support toward and from the table, a device mounted upon the support for contact with articles being stacked, and means controlling the movement of the stacking member and of the stops and including a source of light mounted upon the support and a photoelectric cell receiving light from the source and situated at the opposite side of the conveyor from said source.

19. In an apparatus for stacking box-parts, a

support, means for advancing box-parts successively in a series to the support, means for stopping the box-parts alternately in different positions at the support, stacking means acting upon the stopped box-parts, a member movable to compact the stack, and means controlled by the advancing box-parts for governing the stopping means, the assembling means and the compacting member.

20. The combination with a table, of a conveyor for delivering box-parts successively to the table, a member movable over the table in engagement with the box-parts to form a stack, means for moving the stack-forming member, a member movable to compact the formed stack, means for moving the compacting member, and a photoelectric cell the reception of light by which is varied by the box-parts to control the moving means of both the stack-forming member and the stack-compacting member.

GEORGE S. SILLARS. 

